A lot of people find solace in the beautiful colours of the fall. They walk their favourite trails, or travel to their favourite lookout points to admire the shades of red, orange and yellow. Few ponder the question why the leaves change colour.
When fall comes, it gets a little bit colder and windier. The leaves can’t hold on to their precious branches any more and fall to the ground, giving way to one of the most satisfying noises in human history: the leaf crunch. But have you ever thought about why this happens?
It’s actually quite simple!
As the days get shorter, and less and less sunlight is available, those leaves lose the ability to hold on to that green pigment and their true colours start to reveal themselves. This is when we start to see those famous colours like red and orange. Once the leaves have done their job (producing enough food for the tree to survive the winter), they weaken and eventually allow themselves to fall to the ground.
Then the crunching begins.
But you may still see some leaves on trees through the winter! Weird, right? Well, that is called ‘marcescence.’ This is a term for when the leaves don’t shed from the branch. There are a lot of reasons why this happens. Some scientists blame genetics; some blame evolution. Think about how smart it is for the tree to retain some of its leaves.
Often leaves are held near buds, acting as a sort of shield to protect the tree’s future generations. Just like a person wearing a coat, the leaves provide a protective layer to insulate the buds from the harsh snows of winter, and thereby keep them alive until spring comes! Pretty neat!
So, as you’re out there enjoying the beautiful colours, just remember how much work each leaf is doing to keep those beautiful trees alive. Admire the ones that have fallen, appreciate their sacrifice, and, of course, crunch it, just how it was intended!
Michael Elliott is a naturalist, mass communicator and educator. He spends most of his days learning about the great outdoors and shares his passion for nature with his scouts and friends. He is the creator of the web series “Nature with Rusty.”
This article was originally published in the Friends of Fundy newsletter.